Author:

Songi Han(Dept of Chemistry and Biochemistry and Dept of Chemical Engineering, University of California Santa Barbara)

The hydration water that solvates proteins is a major factor in driving or
enabling biological events, including protein-protein and protein-ligand
interactions. We investigate the role of the protein surface in modulating
the hydration water fluctuations on both the picosecond and nanosecond
timescale with an emerging experimental NMR technique known as Overhauser
Dynamic Nuclear Polarization (ODNP). We carry out site-specific ODNP
measurements of the hydration water fluctuations along the surface of
Chemotaxis Y (CheY), and correlate the measured fluctuations to hydropathic
and topological properties of the CheY surface as derived from molecular
dynamics (MD) simulation. Furthermore, we compare hydration water
fluctuations measured on the CheY surface to that of other globular
proteins, as well as intrinsically disordered proteins, peptides, and
liposome surfaces to systematically test characteristic effects of the
biomolecular surface on the hydration water dynamics. Our results suggest
that the labile (ps) hydration water fluctuations are modulated by the
chemical nature of the surface, while the bound (ns) water fluctuations are
present on surfaces that feature a rough topology and chemical heterogeneity
such as the surface of a folded and structured protein.\\
\\In collaboration with: Ryan Barnes, Dept of Chemistry and Biochemistry, University of California Santa Barbara

To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2017.MAR.B26.2